Insulator



April 8 1924.

A.-O. AUSTIN INSULA'I'OR Filed Sept. 5.

1919 2 Sheets-Sheet l April 8 1924. 1,489,809 A. o. AUSTIN INSULATOR Filed Sept. 1919 2 Sheets-Sheet 2 K Jive/Z zzz zesa flw/Dfw/L m Patented Apr. 8, 1924. i UNITED STATES v 1,489,809 PATENT OFFICE.

ARTHUR. O. AUSTIN, BARBERTON. OHIO, ASSIGNOR, BY MESNE ASSIGNMENTS, TO

THE OHIO BRASS COMPANY, OF MANSFIELD, OHIO, A CORPORATION OF NEW JERSEY.

INSULATOR.

Application filed September 5, 1919. Serial no. 321,837.

device ofthe character named in which resilient means is provided for transmitting stresses from one part to another and which shall be of improved construction 'and operation. v

The invention is exemplified in the combination and arrangement of parts shown in the accompanying drawings and described in the following specification, and it is more particularly pointed out in the appended claims.

In the drawings,

Fig. 1 is a sectional View of one form of insulator embodying the present invention.

Figs. 2, 3 and 4 show insulator pins illustrating modifications of the invention shown in Fig. 1. i

Fig. 5 is a fragmentary sectional view of a different form of insulator having a modification of the invention applied thereto.

Figs. 6, 7 and 8 show insulator ins illustrating other modifications of the invention.

In my prior Patent No. 1,284,976, dated November 19, 1918, I have shown an insulator arranged to distribute stresses transmitted from one partto another in a manner to reduce the danger of cracking or breaking the fragile parts. The present invention provides certain improvements over the in- I sulator shown in the rior patent referred the inner face of the cap 10 is a resilient sheet -metal member .13 corrugated to form inwardly projecting flanges 14 extending.

around the inner face of the cap. The flanges 14 are spaced from -one another, as shown .in the drawings, and may be arranged more closely together near the central portion of the member than they are u adjacent its outer edges. The sheet material 13 is secured to the inner face of the cap 10 in any desirable manner such as by 7 spot Welding, galvanizing or pressing or expanding into grooves.

to. In the drawing, t e numeral 10 desig If the parts are galvanized in any usual way after they have been assembled .the coating material will serve to secure the parts together. The cap 10 is secured to the outer face of the dielectrio member 11 by cement 16 engaging the flanges 14 and the outer face of the dielectric member. In some cases there may be a tendency for the material, with which the flanged sheet is secured to the cap, to be drawn into the open space in the flanges, by capillary action or by a combination of capillary action and atmospheric pressure during cooling. Metal'thus drawn into the flanges would, when it has hardened, imipair the resiliency of the flanges. This may be avoided by placing filling material such as asbestos, cotton, paper or other substance in the space within the flan s. This tendenc may also be overcome y separately galvanizing the parts and subsequently placing them together under sufficient heat to cause them to be secured by thegalvanizing sub stance in the presence of a suitable flux.

Unequal pressure conditions between the interior of the flanges and the outer atmosphere may be avoided by venting the flanges if desired.

Flanges 17 formed by corrugations in a yielding sheet metal member 18 are secured to the periphery of the pin 12 in a manner similar to that of the flanges 14 on the inner face of the cap 10 and the space within the flanges 17 may be filled with the material 15, as explained in connection with the flanges on the cap. The pin 12 is held in the space within the dielectric member by cement 19 engmging the flanges and the inner The flanges face of the dielectric member. 17 are preferably unequally s aced along the pin as explained in connection with the flanges on the cap and this unequal spacing is for the purpose of distributin thev stresses transmitted from the pin to the dielectric member. It will be apparent that the greater stress will be transmitted at the oint where the flanges are most unyieldmg, and that the more closely the flanges are spaced together, the les the amount of. yielding will be and the greater will be the amount ofstress transmitted from one member to the other.

' The arrangement 7 shown in the drawing willpermit the bug est amount of stress to betransmitted at the central portion of the flanged part of sheet m tal thimble 23 is pressed to ing sleeves 21 by which they are secured to the pin. 12, and having inwardly bent portions 29 which provide bearing surfaces for enga ement with the material for connecting e pin with the dielectric member. the form of the invention shown Fig.

corrugations which are arranged in the of threads of a screw The pin 12 is provided with a helical groove onto which the bases of the threads 24 may be screwed to hold the sleeve 23 in place. In this form of the invention the grooves at the bases of the threads 24; are preferably filled with yielding material 26 such as paran'in or war, so that the "fragile material or cement against which the threads 2% bear will not engage the sheet metal member 23 at points where it is rigidly backed by the pin 12. It will be understood that in all of the forms of the invention described, the flanges provided by the corrugated sheet metal not onl ield' as a whole, but give at any point where they are subjected to an excess stress so that it is impossible for the stress to be concentrated at any one point. This is a very valuable feature for the reason that the concentration ofstress at any particular point on a dielectrio member is liable to produce cracking or breaking of the member even when the load carried thereb is not nearly equal to the amount of loa that could be carried if the stress were properly distributed. With a sheet metal connecting member of proper thickness to provide sufiicient resiliency to prevent concentration of stresses the member may, in some cases, be screwed directly into the porcelain without the interposition of cement. The bearing upon the porcelain will be effected entirely by the yielding sheet metal, thus avoiding concentration of stresses such as is present where a rigid member bears directly on the porcelain or cement, or where a rigidmember bears on a face of a thin member or shell directly opposite a point of contact with the cement or other solid material.

In the form of this invention shown in Fig. 5, a sheet metal thimble 27 is formed with thread-shaped grooves having their il1' ner points pinc ed together or compressed to small proportions forming thin ribs- 28 which bear on the bases of the ooves 25 in the pin 12. With this arrangement the necessity of a filling at the root of the grooves in the thimble is removed because of the relatively small size of the ribs 28. The edge of the sleeve may be bent back as shown at 29 to provide a lock for the pin to prevent its unscrewing under load. will be understood that the form of sleeves shown in both Figs. 4 and 5 may be secured in place by other means than by screw threads, such as are described in connection with the other figures of the drawings. This form when applied to the pin or cap by means of screw threads, makes the parts detachable similarly to the parts my prior Patent No. 3,291,? 13, dated January 21, 1919. Unless the portion of the thimble which engages the pin has considerable yield, the stresses will be concentrated on the cement and may cause the dielectric to break. A loosely fitting pin in a sleeve is not sufficient to safeguard the dielectric except on light loads, as any unevenness between tlietwo shells will permit of a localized bearing of the pin giving concentration of stresses owing to the rigid nature of the cement backing the thimble. If distribution of stress is obtained by a good fit between the thimble and the pin, the cement and dielectric will be subjected to stress produced by the expansion or contraction of the large body of metal in the pin. \Vhere a close fit is obtained practically no graduation in the distribution of stress can be obtained for the applied load. The form of device shown in the present invention obviates these difliculties. In Fig. 6 the insulator pin 12 has a helical groove 30 formed thereon and a hollow tube 31 is wound in this groove so that the different turns of the tube contact with one another. The tube is of relatively thin resilient material and may be of various cross sectional shapes. In the drawing, Fig. 6, the tube is somewhat deformed from a circular cross-section to provid ribs 32 fittin in the groove 30 and to provide bearing sur aces 33 for engaging the cement or other holding material with which the pin is connected with the dielectric member. The tube may be fastened at its ends in an suitable mannor to prevent unwinding and sufiicient pressure may usually be secured between the tube and its groove in winding the tube to hold it in place. It may, however, be fastened by brazing, welding, galvanizing or other suitable means in cases where conditions require. A rigid connection of this kind between the'tube and in will lessen the amount that the tube Wlll yield under the stresses to which it is subjected which may be desirable in some cases.

In Fi 7 a tube 34 is wound on the pin 12 butin t is case the inner 'walls of the tube Cir with thin resilient helical ribs 36 and a tube 37 is wound in the groove between these ribs, bearing on the ribs and the base of the groove. This tube may be held in place in any of the ways mentioned in connection with Fig. 6.

In all three of the forms shown in Figs.

I 6. 7 8 a hollow cellular structure is provided having yielding walls for engaging the cement with which the pins are secured to the dielectric member. The fact that only resilient walls contact with th cement prevents concentration of stresses in the cement or insulating member, and the pins with these forms of connection may even be screwed directly into the dielectric member without the interposition of cement. The arrangements shown in connection with pins in Figs. 6, 7 and 8 are, of course, applicable to caps as well as pins.

The cross-sectional areas of the supporting parts such as 10 and 12, as shown'in u the sectional as of the sheet flanges so than the distribu on of the stresses will depend upon the resiliency of the ,flanges and will not be materially affected. by any elongation of the supporting members.

nation. an insulator cmnprisa sheet of thin term ejections on: one ofsaid parts and seart at spaced intervals there-- diute portion of said sheet being resiliei. supported by the attached portions therecf, and means for connecting said projections another of said parts for transmiting stress from one part to the other.

2. An insulator comprising a plurality of parts, a sheet of relatively vthin resilient material coin;= ted with one" of said parts and bent to term flangeahaving spaced walls, projecting from said part, said sheet being secured to said part at the bases of said flanges and 'unattached' thereto at points removed from said bases, and means for connecting said projecting flanges with another of said parts to transmit stress from one of said parts to the other.

3. An insulator comprising a holding member and a dielectric member, a sheet of relatively thin resilient material secured to said holding member and bent to form flanges with spaced walls projecting from said holding member and free to yield to pressure thereon, said sheet h .ving support- "awin s are ireferabl much reater ing connection with said holding member at spaced intervals thereon adjacent the bases of said flanges, and means for securing said holding member with said dielectric member to form a resilient connection between said members.

4. An insulator comprising a holding member and a dielectric member, and a sheet of relatively thin resilient material bent to form flanges with spaced walls, said sheet being fixedly secured to said holding member adjacent one edge of each of said flanges leaving the other edge of each flange free, said flanges being connected with said dielectric member for providing resilient connection between said holding member and said dielectric member.

5. An insulator comprising a holding member and a dielectric member, said holding member having hollow projections thereon secured to said holding member adjacent the bases thereof, and at spaced in tervals along said holding member, and means for securing said projections to said dielectric member, the walls of said projections being free to yield to external pressure thereon.

6. An. insulator comprising a holding member and a dielectric member, said holding member having hollow projections thereon, yielding non-gaseous material with in said hollow projections, and means tor securing said projections to said dielectric member to provide yielding connection between said holding member and said (llfilQCs tric member.

7. insulator comprising a holding member and a dielectric member, projee tions on said holding member formed of relatively thin resilient sheet material constituting yielding walls for said projections, said sheet material being fixedly secured to said holding member adjacent one edge of each of said projections, the other edge of which is yieldingly supported by the intervening sheet ofinaterial, the points of connection with said holding member being distributed at spaced intervals along said holding member, and means for connecting said projections with said dielectric member so that said projections will transmit stress from one of said members to the other.

8. An insulator comprising a holding member and a dielectric member, a connection between said members comprisin a sheet of relatively thin material secure. to said holding member and bent to form hollow yielding flanges projecting from said between said members comprising a sheet of relatively thin resilient material having portions thereof secured to said holding member and intermediate portions thereof bent to form hollow flanges projecting from said holding member, said flanges being connected with said dielectric member and differing from one another to provide dilferent I degrees of resiliency in the connection being member, and means for connecting said said holding member and bent to form (proprojections with said dielectric member, said projections being differently arranged at different points on said holding member to provide different degrees of resiliency between said holdin member and said dielectric member at di' erent points on said holding member.

11. An insulator pin comprising a rigid member, and a sleeve formed of a sheet of relatively thin resilient material secured to said rigid member at spaced intervals along the length of said ri id member with intervening portions of said sleeve free to yield relative to said rigid member and bent to form hollow resilient projections extending from ,said rigid member, the points of attachment being distributed along said rigid member in spaced relation to one another.

12. An insulator pin comprising a rigid member, and a sleeve of relatively thin resilient material bent to form erlpheral corrugations on said sleeve, said 5 eeve having the edges of said corrugations on one face of said sleeve, fixedly secured to said rigid member.

13. An insulator comprising a dielectric member and a holding member, a sleeve of relatively thin resilient material secured to jections extending therefrom, and yiel ing material arranged to cover said sleeve adjacent points of contact between said sleeve and said holding member while portions of said projectionsspaced away from said holding member are free from said yielding material so as to form connection with 'said dielectric member.

14. Ali, insulator comprising a holding member, a sheet of relatively thin resilient material connected with said holding member and corrugated to form projections extending therefrom, and a coating of yielding material at the bases of said projections adjacent points of contact between said holding member and said sheet of resilient material, the extremities of said projections being free from said yielding material.

15. An insulator comprising a plurality of parts and a member for transmitting stress from one of said parts to another, said member comprising hollow portions, each having a relatively thin resilient wall with a portion of one face thereof arranged to bear on one of said arts, while the opposite face of said wal adjacent said bearing portion is free from rigid support, said member being rigidly secured to each of said parts at intervals distributed over the surfaces thereof to facilitate transmis sion of force from one to the other thereof.

16. An insulator comprising a plurality of parts and a member for transmitting stress from one of said parts to another, said member comprising hollow portions each having a relatively thin resilient wall, portions of the outer face of which are arranged to bear upon one of said parts, while the inner face of said wall ad acent said bearing portions is free from rigid support, leaving said bearing portions free to yield under force exerted thereon, the inner face of said wall being rigidly connected with the part adjacent thereto at distributed points over the surface of said part to facilitate transmission of stresses from one of said parts to the other.

17. An insulator comprising a pair of parts, a closed thimble of sheet material on one of said parts, said thimble having portions arranged to contact with the other of said parts to transmit stress from one of said parts to the other, said contacting portions of said thimble bein free to yield 'under the stress transmitte thereby while other portions of said thimble are rigidly connected with said first-mentioned part at points alternating with said contacting portions.

18. An insulator comprising a pair of parts, a thimble of sheet material bent to form hollow flan es on one of said parts, said flanges having portions thereof arranged to contact with the other of said parts to transmit strem from one of said parts to the other, said contacting rtions of said flanges being free to yield under the stress transmitted thereby and rigid connections between said thimble and said first-mentioned part adjacent the bases of said flanges.

19. An insulator comprising a pair of co-operating parts and a resilient sleeve interposed between said parts for transmitting stress from one of said EItStO the other, said sleeve being arran to contact with each of said parts at ifl'eren't posiportion at spaced intervals along the length tions thereon and spaced therefrom at intermediatepositions, the points of contact with the two parts alternating with one another for transmitting stress from one of said parts to the other, said sleeve being subjected to higher stress per unit section than the parts connected thereby,

20. An insulator comprising a dielectric member, and a member for transmitting stress to said dielectric member, said last named member com rising a main body portion and a close thimble of resilient material carried thereby, said thimble havin contact portions thereof connected with said dielectric member and. subjected to higher stress per unit section than said main body portion, to provide resilent connection between said dielectric member and said main body (portion, said thimble being rigidly secure to said main body of said body portion.

21. An insulator comprising a holding member, a dielectric member, and means for securing said members to one another, said securing means comprising a relatively thin sheet of material bent to provide hollow portions havin contact parts thereof, connected with sai dielectric member, the

face of said sheet opposite said dielectric ,face are rigidly secured to said holding member.

7 22. An insulator comprising a plurality of parts, a resilient sheet metal member connected with one of said parts and ar-' ranged to form' a hollow cellular structurehaving yielding walls secured to said part adjacent each ,cellular division, and means for connecting the yielding walls of sa d cellular structure with another of said parts for transmitting stress between said parts.

23. An insulator comprising a holding memberand a dielectric member, said holding member having hollow cellular projections thereon with resilient walls secured to said holding member adjacent each cellular division, and connecting material engaging said walls for securing said holding member with said dielectric member.

In testimony whereof I have signed my name to this specification on this 18th day of August, A. D. 1919.

. ARTHUR O. -AUSTIN.- 

